Update project list in the header bar.

Use function for clean cache (from openstack_auth), after project
members were changed(for project cache is invalidated).
Now, in the header bar, show only active projects.

Change-Id: Ia2561b591b4f3de29a14aaa4b666b16fc1d4cec8
Closes-Bug: #1393659
Documenting create_stubs decorator for tests

Closes-Bug: #1398912
Change-Id: I0ae1cb2da9693f5d2904cd96d475519b753a589d
Added tests for Node Group Templates' create and copy workflows

test_copy has been adapted from cluster_templates and
only checks for the ng name

Closes-Bug: #1382377

Change-Id: Ibb33241efdf2990004de431f1268fb3e3a2d6781
Merge "Added tests for Node Group Templates' create and copy workflows"
Merge "Update project list in the header bar."
Merge "Documenting create_stubs decorator for tests"
Merge branch 'master' of https://github.com/openstack/horizon